1872.] ETHERIDGE atJEENSLAND FOSSILS. 335 



The mesial fold is not so well defined as in the typical Sp. striata ; 

 and some transverse forms of Sj). bisulcata assume this shape. We 

 may, however, confidently refer it to the above shell, or one of its 

 many varieties. 



This most variable and widely distributed species of the genus 

 Spir-ifera appears to be not uncommon, as I have been given to under- 

 stand that individuals of the species are abundant in the Bowen- 

 B,iver series. This shell is typical of the Carboniferous rocks in 

 every region of the globe where deposits of this age occur. 



The hinge-line is as long as the greatest width of the shell, and 

 the cardinal angles somewhat acute ; the ribs on the surface of our 

 shell are finer than in most specimens ; it resembles some Yorkshire 

 as well as American forms ; but we have had no opportunity of com- 

 paring it with Russian specimens. 



Log. Eowen Eiver, Peak Downs. Form. Carboniferous. 



Spieifeea convolxjta? Phill. PI. XYII. fig. 3. 



Bef. Geol. Yorkshire, vol. ii. p. 217, t. 9. fig. 7 ; Dav. Mon. Brit. 

 Garb. Brach., Pal. Soc. p. 35, t. 5. figs. 2-15. 



We may refer this fragment to Sp. convoluta ; its extreme width 

 and straight hinge-line essentially ally it to this sheU ; the acute 

 angles at the extremities are lost ; still many of our Yorkshire shells 

 strongly resemble this species : the ribs on the mesial fold are also less 

 defined than on most typical forms ; it is, however, closely allied 

 to our British species. 



We have only a portion of the shell by which to compare it with 

 British and Belgian shells ; but the identification cannot, I think, be 

 doubted. 



Loc. Bowen River. Form. Carboniferous. 



Spieifera allied to S. bisulcata, Sow. PI. XYII. fig. 4. 



Bef. Min. Conch, t. 492. figs. 1, 2; Dav. Mon. Carb. Brach., Pal. 

 Soc. p. 31, t. 6. figs. 1-19. 



The ventral valve only of this shell occurs ; and I refer it to one 

 of the many forms of Sp. bisulcata as being the nearest ; we figure 

 it as an important example from the Carboniferous rocks and for future 

 research. The incurved and approximate beaks are well shown, also 

 the numerous and fine ribs upon both sides of the mesial fold. Un- 

 fortunately the cardinal area is not seen, but the complete description 

 of the varieties and forms of this shell by Thomas Davidson, Esq., 

 r.E.S., in his valuable memoir upon the Carboniferous Brachiopoda, 

 Pal. Soc. p. 31, t. 6. figs. 1-19, supplies the want of better specimens. 



Our shell possesses scarcely so elongated a hinge-line as most of 

 the forms of this species ; but the rounded cardinal extremities, or 

 angles, wide area and incurved beak, as well as the facies, leave 

 little doubt about its alliance. This, like many species of Spirifera, 

 is extensively distributed in time and space, especially through the 

 Carboniferous series of Europe. 



Loc. Bowen River. Form. Carboniferous. 



